Brake



Oct. 7, 194 1. L. R. WILLIAMSON 1 BRAKE fie. E

INVENTOR. (ARK/1v A? Mum/wow Filed Feb. 2, 1939 ATTO EY.

Patented Oct. 7, 1941 BRAKE Larkin R. Williamson, Brooklyn, N. yassignor to E. W. Bliss Company, Brooklyn, N. Y., a corporationof.Delaware Application February 2, 1939, Serial No. 254,274

3 Claims.

This invention relates to mechanism for coupling a driving shaft and adriven shaft of a machine tool or the like to connect a source ofpowerwith a tool to be driven. The invention is particularly adapted for usein presses, shears and the like, which are operated through a single orrelatively short cycle and are then stopped to remove the finished workand substitute new work.

In general, my invention is directed to a planetary gear system withwhich is incorporated a brak mechanism adapted .to clamp one of theplanetary gear train members against rotation, as desired.

Planetary gears as a drive means are very old and my invention is notdirected to such a train per se but rather is directed tothe combinationof a train with the clamping brake system by which the same is rendereduseful for the purposes outlined above.

More specifically in transmitting heavy loads, it is desirable to applyth clamping thrust on a gear train in such a manner that there is aminimum of strain with a consequent elimination of any torsion effect inthe shafts and parts of the device. I have found that by providing apair of operative shoes, either as a single pair or as several pairs, itis possible to obtain an improved clamping action which may be readilyemployed with a heavy duty machine without 30 the resultantdisadvantages heretofore encountered. p

My improved device thus in general employs an outer floating internalgear which is clamped and retained against movement when the drive 35 iseffected between the driving and driven parts.

Fluid pressure applied from a cylinder against a respective piston urgeseach of two aligned brake shoes into engagement with the floating gearto clamp the same as desired.

The general object of my invention has been to provide a simplifiedbrake and associated mechanism and with this general object in viewother objects will becom apparent from the following specification andfrom the drawing.

To the accomplishment of the foregoing and related ends, said invention,then, consists of the means hereinafter fully described and particularlypointed out in the claims; the annexed drawing and the followingdescription setting forth in detail certain structuraemhodying theinvention, such disclosed means constituting,

In said annexed drawing: Fig. 1 is a transverse section through myimproved mechanism; and

Fig. 2 is a section through Fig. l as indicated by the lines 2---2thereon. The drawing generally shows a main housing 5 suitably securedto the frame F of the ma-' chine with which my invention is employed.The housing is rigidly secured to the frame to eliminate, in so far aspossible, any driving strain in the parts with a resultant eifect on thelife of the machine and its operation. The housing is open at the faceremote from the machine portion 1 and is provided with a closely fittedremovable capb to seal this opening and support the part while readilypermitting access thereto,

The upper portion of the housing is provided '20 mounted in ballbearings 22 and 24.

with an enlarged boss 9 in which is journalled a stub shaft it. One endof the shaft is supported in a sleeve bearing H in the housing and theother end is carried in a ball bearing H in the cap 8. The shaft xtendsbeyond the cap and carries a pulley wheel l4 suitably keyed thereto forrotation. The pulley is driven by a series of V-belts passing thereoverand engaging corresponding grooves in the outer surface and,.inconjunction with the shaft it], provides the driving part of thmechanism. Interposed between the pulley wheel and the bearing i2 is acap l6 which may be readily removed from the main cap to permit accessto the bearing for greasing.

The shaft H) has keyed thereto a pinion I! which is positioned betweenthe bearings I l and I 2. This pinion is 'in mesh with and drives alarge gear l8 which is keyed to a short stub shaft The former set ofbearings are carried in the cap 8 while the'latter set aremounted in aportion of 40 th driven mechanism as hereinafter described.

however, but one of various mechanical forms in which the principle ofthe invention may be used.

The hub and toothed portion of'the gear l8 are connected by an ofl-setweb which provides space for partially mounting over the gear'hubhereinafter to be described. Also keyed to the shaft iii-is a pinion 25which lies closely against the inner portion ,of the opening iii of thegear l8.

The driven shaft of the mechanism which connects with the operativeportion of the machine tool is represented at 21 and terminates just'within the housing at 28. Closely overlying the end of the shaft is aflanged sleeve 30 which is keyed thereto as at 3!. The outer portion ofthe sleeve is concentric with the shaft and carties the inner races of apair of tapered thrustbearings 32. The outer races are received withinan enlarged opening 34 formed in an inwardly extending sleeve portion ofthe housing. The outer periphery of this sleeve portion in turn closelyfits the machine frame 1 to provide a concentric assembly consisting ofthe shaft 21, the sleeve 3|, the bearings 32, the housing sleeve and thecorresponding opening in th frame 1. The sleeve 30 passes within thehousing andv flares outwardly to form a radial flange 3B. A recess isprovided concentric with the shaft 21 at the right hand face of theflange (Fig. l) and this recess carries the outer race of the ballbearing unit 24 heretofore described, which permits the shafts 20 and 21to rotate freely with respect to each other, although they are inalignment.

Three cluster gears 35 are carried by the flange 36 and rotatetherewith. Each gear is rotatably mounted on a pin 38, which is reducedin, cross section at each end and one end of which is carried in theaforesaid flange. The other end of each pin is carried in a reinforcingplate 31 in such manner that the 'three gears are spaced 120 apart andare each in mesh with the pinion 25.

To maintain the reinforcing plate and the flange with respect to eachother, the plate is provided with three roughly triangular extensions 40which lie in face to face contact with the flange and are of sufiicientdepth to allow the cluster gears to run freely. The Pla e and flange arebolted together by nine bolts 42 passing througheach of the triangularportions and additionally three dowels M are provided to secure theplate and fl e me t-her as n. mics-re uni nd to reinforce the bolts.

' A large internal gear 50 is rotatably mounted on a housing in araceway formed at El which is provided with a lip portion to preventmovement of the gear to the left (Fig. 1). This gear is provided on itsinner annular face with teeth 52 which engage each of the pinions 35 andresult in the gear 50 being normally slowly rotated by reason of thedrive from the pinion 25 which rotates the pinions 35. The mounting ofthe parts is such that the gear 50 rotates more easily in its racewaythan does the shaft 21 connected with the working parts of the machine.Accordingly, in normal operaion the gear 50, the cluster gears 35 andthe pinion 25 are all in rotation while the shaft 21 remains still. Whenthe gear 50 is clamped against rotation, however, the driving force ofthe pinion 25 rotates the cluster gears thereabout resulting in a driveto the machine parts through the shaft2-1.

To drive the machine tool carrying the mechanism under discussion, apair of opposed friction shoes 55 are urged into clamping relation withthe outer annular face of the gear 50. These shoes are slidable in waysare each provided on its suitable friction material 1. The ways 58extend through the housing which is open at their outer ends to allowinsertion of the shoes. Such openlogs are normally sealed by a removablecap 5.8 in each ofwhich is formed a cylinder 58, which in turn carries arespective piston 80. Each cylinder ,in turn is sealed by a similar cap.5,2 which may be secured thereto. clamped-between the two caps is adiaphragm which extends across the cylinder to provide a sealeliminating leakage inwardly between the piston and-its associatedcylinder wall. Fluid under pressure is admitted through an opening "toeach cylinder and upon its admittanceeach piston forces arespectiveshoe-into clamping. relati w h thin- 56. in the housing and. earengaging face with ternal gear 50 to lock the same against rotation.

As best shown in Fig. 2 the shoes and pistons lie in alignment with eachother along a line passing radially through the axis of the shaft 21 andgear 50. If more than two pistons are employed, they shouldbe spacedsuch that there is no sidewise thrust in the parts during engagement.Thus, if an even number of pistons are used, they should be mounted inaligned pairs and if an uneven number of pistons are employed, such asthree, they should be equally spaced about the gear periphery.

To limit the outward movement of the parts when the mechanism standsidle, a bolt 68 is provided and mounted in a central boss 69 of the cap62. at its inner end the bolt engages a clip "which may be adjustedinwardly or outwardly to control the amount of return in respectivepistons when the pressure is released and the drive is broken.

From the foregoing description it will be seen that I have devised anovel form of planetary drive mechanism and that with such mechanism Ihave devised a novel clamping means to control a housing, a rotatablemember therein provided.

with a friction surfacasaid housing being formed with a generally radialbore and with the sides of said bore sp'aced'apart to provide a pair ofslideways for receiving a shoe mounted for movement toward .and fromsaid friction surface, a shoe slidably carried between said slidewaysand supported and aligned thereby at r zions adiacent the ends thereoffor sliding movement along said slideways, a c inder carried by idhousins, a piston in said cylinder mounted for movement toward and fromsaid one friction surface and a face on said piston adapted to engagesaid shoe to urge the same into. friction contact with said friction.surface and means for actuating said piston.

2. In a driving mechanism, the'combinatlon of a housing, a rotatablemember therein provided w th a. friction. sur ac aid hous ns einz o medw h u al ty bores exte d in a i c i generally radial of the a is ofrotation of said me r a d. with t e. ides or sol bores spac a t o proide spe tively a. o slideway or e c i c shoe m unted for m ve nt to-Word and m. one fricti n urface. a ho lidab v earned between t eSideways. in each bor and. suppor ed an shamed e by. at rea one colaent.the. ends t ere f for. sliding mo eent al n s id. slisiswers. respectiely owar s said friction. surface. a plura it of mind i alignment withsaidbores e pectivel a p sto in ach. c li der m unted. for movementtoward ete aodm s ndv f qmseidr ctionsuriace ands ace onsaid a.nousma-adr vc oemben carded h reby with a. f ictionhsuriaoe orm d. onmPo i n thereof, a pair of diametrically spaced QIQ-i formed in saidhousing with the sides of each of therealong, a pair of cylinders formedin said v said bores spaced from the other respectively to housing, oneextending coincident with the axis provide a pair of opposed slidewaysfor receiving of travel of said shoes respectively, and a face shoesmounted for movement toward and from on each of said pistons adapted toengage saidsaid friction surface, a shoe slidably carried in 5 shoesrespectively to urge the same into friction each bore and supported andaligned adjacent its contact with said friction surfaces v ends by saidslideways for sliding movement LARKIN R. WILLIAMSON.

